The validity of this trial could be affected by the fact that several midwives perform the interventions. But numerous birth assistants are the reality at most centres, thereby increasing the external validity and generalizability of the trial. Additionally, it might be interpreted as a limitation that this is a single-centre trial, although it increases internal validity of the trial. tThe perineal tears are evaluated by several objective assessors (midwives or doctors), which possibly might affect the validity of the outcome assessment. We will try to overcome this issue by validating the registered higher degree tears (3rd and 4th degree) by examining the patient records. Additionally, we are planning to retrieve data on all 3rd and 4th degree tears in our study population during the study period from the hospital registers and validate this data against patient records. We assume that especially higher degree tears may be diagnosed after trial assessment. These tears will be registered centrally because registration commonly takes place after lesion repair. Thus, all higher degree tears included in our final analysis will be validated.